A wide variety of implantable medical devices (IMDs) that employ electronic circuitry for providing electrical stimulation of body tissue and/or monitoring a physiologic condition are known in the art. IMDs may include implantable pulse generators (IPG), cardiac pacemakers, pacemaker-cardioverter-defibrillators, nerve, muscle and neurological stimulators, cardiomyostimulators, implantable drug dispensers, implantable cardiac signal monitors and recorders, and the like. IMDs typically include a housing that encloses a variety of internal components and isolates them from the implanted environment. IMDs may include integrated circuits, charging capacitors, batteries, and other components that are enclosed in hermetically sealed metallic housings. Within the human body, for example, the housing must be sealed to prevent ingress of fluids that can cause the device to short circuit or corrode internal components, which renders the IMD inoperable.
The IMDs typically comprise a hermetically sealed housing containing the battery and electronic circuitry. Many IMDs are capable of two-way communication or telemetry between the IMD and an external device, (e.g., a programmer). For example, in a pacemaker system, a programmer downloads data to an implanted pacemaker such as operating parameters. Likewise, data may flow in the opposite direction; that is, from the implanted pacemaker to the programmer for analysis. In fact, modern IMD's are capable of storing significant amounts of data about the patient (e.g., average heart rate) and the pacemaker itself (e.g., battery voltage), which may need to be frequently transmitted to the programmer or other device for evaluation by the physician.
One way of communicating with an IMD is through RF telemetry transmission, which relies upon magnetic field coupling through the patient's skin of an IMD IPG antenna with a closely spaced programmer antenna or broadcast telemetry over a greater distance from the IMD to a receiver. The RF telemetry antenna is positioned outside the hermetically sealed IMD housing, which allows it to operate in a high frequency RF telemetry bandwidth and reduces space requirements inside the housing. The RF telemetry antenna is connected to an antenna feedthrough. RF telemetry circuitry on an RF module is positioned inside the hermetically sealed IMD housing. The RF module must be coupled to the antenna feedthrough. This can be a problem due to the positioning of the RF module in relation to the antenna feedthrough and the small amount of space inside the housing.
Accordingly, it is desirable to provide a flexible radio frequency (RF) antenna flexible circuit interconnect between an RF module inside an IMD housing and an antenna feedthrough for an RF telemetry antenna located outside the IMD housing. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.